Differences in Schistosomiasis Knowledge among Irrigation Rice Farming Communities in Different Irrigation Schemes in Tanzania.

Aim: To assess differences in schistosomiasis knowledge in farmers working in traditional, improved traditional and modern irrigation schemes in Tanzania. Study Design: A cross-sectional survey among farmers practicing irrigation rice farming, in 2 different regions and 6 different irrigation systems. Place and Duration of Study: The study was carried out between November and December 2011 in the Morogoro and Kilimanjaro Regions, Tanzania. Methodology: Equal number of irrigators in each scheme was employed. Irrigators were chosen randomly by the researcher from the list of all farmers actually engaged in rice irrigation farming provided by the village governments in the six schemes. Two hundred and fourty samples (240) were used, 120 from each region (40 farmers practicing irrigation rice farming in each scheme). Independent sample t-test was used for testing schistosomiasis knowledge differences among irrigators between schemes with the same design and construction of their infrastructures between the two regions. Results: More than 88% of irrigators surveyed in Kilimanjaro schemes had better knowledge regarding to all schistosmiasis items asked compared to those in Morogoro, particularly Chabi scheme-traditional. There were significant difference on irrigators knowledge on schistosomiasis symptoms (P<0.001), and predisposing factors (P<0.001) between Morogoro and Kilimanjaro Modern schemes. Knowledge on predisposing factors differed significantly (P<0.001) between irrigators in Morogoro and Kilimanjaro improved traditional schemes. Moreover significant difference were noted on irrigators knowledge on schistosomiasis symptoms (P<0.001), predisposing factors (P<0.004) and schistosomiasis control measures (P=0.003) between irrigators in Morogoro and Kilimanjaro traditional schemes. Conclusion: From the results it appears that the level of farmers’ knowledge of schistosomiasis is related to: proximity to health facilities of the community, trainings that have been provided to farmers and farmer’s literacy rate. However the government should be responsible to improve health facilities, construct roads and deliver schistosomiasis education to communities in irrigation areas even for schemes which have not been planned, designed and constructed by the government.

Effect of chlorination of drinking-water on water quality and childhood diarrhoea in a village in Pakistan.

To evaluate the importance of public-domain transmission of pathogens in drinking-water, an intervention study was carried out by chlorinating the public water-supply system in a village in Pakistan. The water quality improved and reached a geometric mean of 3 Escherichia coli per 100 mL at the last standpipe of the water-supply system. Drinking-water source used and the occurrence of diarrhoea were monitored on a weekly basis over a six-month period among 144 children aged less than five years in the village. In this group, the children using chlorinated water from the water-supply scheme had a higher risk of diarrhoea than children using groundwater sources, controlled for confounding by season and availability of a toilet and a water-storage facility. The incidence of diarrhoea in the village (7.3 episodes per 10(3) person-days) was not statistically different from that in a neighbouring village where most children used water from a non-chlorinated water-supply system with very poor water quality. In this study area, under non-epidemic conditions, the reduction of faecal bacteria in the public drinking-water supply by chlorination does not seem to be a priority intervention to reduce childhood diarrhoea. However, the study was of limited size and cannot provide conclusive evidence.

Role of wastewater irrigation in mosquito breeding in south Punjab, Pakistan.

Mosquito breeding within the wastewater irrigation system around the town of Haroonabad in the southern Punjab, Pakistan, was studied from July to September 2000 as part of a wider study of the costs and benefits of wastewater use in agriculture. The objective of this study was to assess the vector-borne human disease risks associated with mosquito species utilizing wastewater for breeding. Mosquito larvae were collected on a fortnightly basis from components of the wastewater disposal system and irrigated sites. In total, 133 samples were collected, about equally divided between agricultural sites and the wastewater disposal system. Overall, 17.3% of the samples were positive for Anopheles, 12.0% for Culex and 15.0% for Aedes. Four anopheline species, viz, Anopheles stephensi (84.3% of total anophelines), An. subpictus (11.8%), An. culicifacies (2.0%) and An. pulcherrimus (0.2%) were present, as were two species of Culex, viz, Cx. quinquefasciatus (66.5% of culicines) and Cx. tritaeniorhynchus (20.1%). Aedes were not identified to species level. The occurrence of different species was linked to particular habitats and habitat characteristics such as physical water condition, chemical water quality and the presence of fauna and flora. Anophelines and Aedes mosquitos were mainly collected during the month of July, while Culex were collected in September. The prevalence of established vectors of human diseases such as An. stephensi (malaria), Cx. tritaeniorhynchus (West Nile fever, Japanese encephalitis) and Cx. quinquefasciatus (Bancroftian filariasis, West Nile fever) in the wastewater system indicated that such habitats could contribute to vector-borne disease risks for human communities that are dependent upon wastewater use for their livelihoods. Wastewater disposal and irrigation systems provide a perennial source of water for vector mosquitos in semi-arid countries like Pakistan. Vector mosquitos exploit these sites if alternative breeding sites with better biological, physical, and chemical conditions are not abundant.